Publication Date:
2008-10-22
Description:
Double-strand breaks activate the ataxia telangiectasia mutated (ATM) kinase, which promotes the accumulation of DNA damage factors in the chromatin surrounding the break. The functional significance of the resulting DNA damage foci is poorly understood. Here we show that 53BP1 (also known as TRP53BP1), a component of DNA damage foci, changes the dynamic behaviour of chromatin to promote DNA repair. We used conditional deletion of the shelterin component TRF2 (also known as TERF2) from mouse cells (TRF2(fl/-)) to deprotect telomeres, which, like double-strand breaks, activate the ATM kinase, accumulate 53BP1 and are processed by non-homologous end joining (NHEJ). Deletion of TRF2 from 53BP1-deficient cells established that NHEJ of dysfunctional telomeres is strongly dependent on the binding of 53BP1 to damaged chromosome ends. To address the mechanism by which 53BP1 promotes NHEJ, we used time-lapse microscopy to measure telomere dynamics before and after their deprotection. Imaging showed that deprotected telomeres are more mobile and sample larger territories within the nucleus. This change in chromatin dynamics was dependent on 53BP1 and ATM but did not require a functional NHEJ pathway. We propose that the binding of 53BP1 near DNA breaks changes the dynamic behaviour of the local chromatin, thereby facilitating NHEJ repair reactions that involve distant sites, including joining of dysfunctional telomeres and AID (also known as AICDA)-induced breaks in immunoglobulin class-switch recombination.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2613650/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉 〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2613650/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Dimitrova, Nadya -- Chen, Yi-Chun M -- Spector, David L -- de Lange, Titia -- DP1 OD000379/OD/NIH HHS/ -- DP1 OD000379-04/OD/NIH HHS/ -- EY18244/EY/NEI NIH HHS/ -- GM049046/GM/NIGMS NIH HHS/ -- GM42694/GM/NIGMS NIH HHS/ -- OD000379/OD/NIH HHS/ -- R37 GM049046/GM/NIGMS NIH HHS/ -- R37 GM049046-16/GM/NIGMS NIH HHS/ -- Howard Hughes Medical Institute/ -- England -- Nature. 2008 Nov 27;456(7221):524-8. doi: 10.1038/nature07433. Epub 2008 Oct 19.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉The Rockefeller University, 1230 York Avenue, New York, New York 10065, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/18931659" target="_blank"〉PubMed〈/a〉
Keywords:
Animals
;
Cells, Cultured
;
Chromatin/genetics/*metabolism
;
Chromosomal Proteins, Non-Histone
;
DNA Breaks, Double-Stranded
;
*DNA Damage
;
*DNA Repair
;
DNA-Binding Proteins
;
Humans
;
Intracellular Signaling Peptides and Proteins/deficiency/genetics/*metabolism
;
Mice
;
Movement
;
Protein Binding
;
Sequence Homology
;
Signal Transduction
;
Telomere/*genetics/*metabolism
;
Telomeric Repeat Binding Protein 2/deficiency/genetics/metabolism
Print ISSN:
0028-0836
Electronic ISSN:
1476-4687
Topics:
Biology
,
Chemistry and Pharmacology
,
Medicine
,
Natural Sciences in General
,
Physics
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